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Hey, I am fairly new to RSS/RO, and more specifically rocket design. How do you guys make such small orbital capable launchers? My smallest is 57 tons and 27 meters tall, and 2m diameter at the first stage.

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Hey, I am fairly new to RSS/RO, and more specifically rocket design. How do you guys make such small orbital capable launchers? My smallest is 57 tons and 27 meters tall, and 2m diameter at the first stage.

Some of the parts are different now, but it should give you an idea of how to do it. Otherwise, it's hard to give you more specific suggestions without knowing what is the mass of payload you want to put in orbit, and if you are limiting yourself with regards to tech level.

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Ok, I am just using whatever tech, the best I can find, and I am launching a probe weighing 0.1t to a 200-230km orbit. One of my difficulties is engine selection, other than LR89 or 79, and the AJ10 series of engines. and the generic thrusters, the 1.xx and the 2.xx kn thrusters

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Ok, I am just using whatever tech, the best I can find, and I am launching a probe weighing 0.1t to a 200-230km orbit. One of my difficulties is engine selection, other than LR89 or 79, and the AJ10 series of engines. and the generic thrusters, the 1.xx and the 2.xx kn thrusters﻿

Another strategy is to use the baby sergeants as a kick stage to circularise at AP (you can even use multiple stages of them).

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I guess this has been asked before but what will be condition to update Realism Overall to a more recent version of KSP. My feeling is KSP 1.6 t the last major version of KSP, there mighr follow some patches but I don't think there will be any 1.7.

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How do you guys make such small orbital capable launchers? My smallest is 57 tons and 27 meters tall, and 2m diameter at the first stage.﻿

1. Use as modern stuff as possible

2. Make your probe as light as possible. For instance cubesats from AIES can be scaled down to about 0,25 kg.

3. Use Procedural Avionics to create as light as possible guidance unit. Do not attach it to the last stage - use spin stabillisation instead.

4. Use solid fuel. Procedural SRBs can be easily miniaturized so you can create very small upper stages.

5. Use supersonic or hypersonic plane as a first stage. Staging at Mach 2.0 will save about 30-40% of LV weight, staging at Mach 6 - about 60%.

Here is an example. 775 kg launcher (orange rocket) - 15 kg payload. Just about the size of a sounding rocket and with a 0,25 kg payload it could be 2-3x lighter.

But if you're limited by early tech... that's a full different story. I remember that my first orbital capable launcher was just a replica of Vanguard: 10t vehicle - 3 stages: X-405, AJ-10, solid upper stage.

Spoiler

Edited December 24, 2018 by winged

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I guess this has been asked before but what will be condition to update Realism Overall to a more recent version of KSP. My feeling is KSP 1.6 t the last major version of KSP, there mighr follow some patches but I don't think there will be any 1.7.

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Ok, I am just using whatever tech, the best I can find, and I am launching a probe weighing 0.1t to a 200-230km orbit. One of my difficulties is engine selection, other than LR89 or 79, and the AJ10 series of engines. and the generic thrusters, the 1.xx and the 2.xx kn thrusters

One of the most fun things in RO is using knowledge of what real engines are best at then using them appropriately.

NK-33 and Merlin 1D are the some of my favorite lower stage engines. One of the things that can kill you on getting into orbit is upper stage TWR. In my experience, it should be as low as possible, since that means that you probably have a lightweight engine, which is important.

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Quit frankly this feature in mechjeb is a outright disaster when using realism overhaul engines. Im trying to get a set of Raptor engines to achieve powered landings using Mechjeb so I dont have to play suicide games with the suicide burn timers.

How do I get rid of that delayed engine startup? Mechjeb hates powered landings because it does not account for that delay. I also had to get rid of the limited ignitions as mechjeb was just firing all the ignitions like a machine gun! Basically I need the Space X Raptor engines from KK Lanchers pack with the ITS ship to land like it needs to.

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Quit frankly this feature in mechjeb is a outright disaster when using realism overhaul engines. Im trying to get a set of Raptor engines to achieve powered landings using Mechjeb so I dont have to play suicide games with the suicide burn timers.

How do I get rid of that delayed engine startup? Mechjeb hates powered landings because it does not account for that delay. I also had to get rid of the limited ignitions as mechjeb was just firing all the ignitions like a machine gun! Basically I need the Space X Raptor engines from KK Lanchers pack with the ITS ship to land like it needs to.

You are completely right. Mechjeb doesn't have any logic internally to account for the RO-Engines features, so if you want to use Mechjeb successfully this is my recommendation:

- Disable limited ignitions (you can disable the limited ignitions for every engine changing the RealFuels settings I think)

- Disable unstable ignitions,etc.

- Create a MMPatch for the engines you want to use in order to: set minThrust to 0 if it has a greater number, disable throttleResponse, disable throttleCurve.

- If you experience problems with the gimbal , you will need to remove the gimbalresponserate too.

- Regarding the delayed engine startup. I haven't managed to completely solve this problem. What I recommend is to switch from Landing At X to Land somewhere when you are close to land ( altitude < 10k) also I recommend to have a TWR at landing not greater than 2.2-2.5 because it will be too late when Mechjeb starts the engine.

Once you have done all this things you will have a Mechjeb-friendly setup which will allow you to do things like this video I recorded last week.

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You are completely right. Mechjeb doesn't have any logic internally to account for the RO-Engines features, so if you want to use Mechjeb successfully this is my recommendation:

- Disable limited ignitions (you can disable the limited ignitions for every engine changing the RealFuels settings I think)

- Disable unstable ignitions,etc.

- Create a MMPatch for the engines you want to use in order to: set minThrust to 0 if it has a greater number, disable throttleResponse, disable throttleCurve.

- If you experience problems with the gimbal , you will need to remove the gimbalresponserate too.

- Regarding the delayed engine startup. I haven't managed to completely solve this problem. What I recommend is to switch from Landing At X to Land somewhere when you are close to land ( altitude < 10k) also I recommend to have a TWR at landing not greater than 2.2-2.5 because it will be too late when Mechjeb starts the engine.

Once you have done all this things you will have a Mechjeb-friendly setup which will allow you to do things like this video I recorded last week.

I don't want to sound rude, but basically you are suggesting to disable RO to get powered landings on RO...

My suggestion @lextacy would be to start playing around with KerbalOS - I know it might prove a tad challenging, but boy oh boy the feeling when you get it right!

EDIT: also was not there a "RO-mode" under MechJeb's settings that handles ullage & ignitions? I might be completely wrong here.

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I got a custom window set up in mechjeb with velocity, suicideburn countdown, time to impact en altitude.
It helps you to count down a full suicide burn almost perfectly, most of the time I start the burn on half throttle 3 second ahead, then finetune it to 0.0 sec countdown so it lands perfectly.